The repetitive domain of Trypanosoma cruzi trans-sialidase enhances the immune response against the catalytic domain.
Trypanosoma cruzi trans-sialidase consists of a C-terminal domain composed essentially of immunodominant amino acid repeat units (SAPA-repeats) and an amino region responsible for the enzymatic activity (catalytic domain). To investigate the possible function(s) of SAPA-repeats, recombinant trans-sialidases either containing or lacking the C-terminal region were tested in mice. The presence of SAPA-repeats in the intravenously injected protein has two consequences. First, they enhance the persistence of the trans-sialidase activity in blood. Second, SAPA-repeats promoted the production of antibodies directed to the catalytic domain that inhibit trans-sialidase activity. These results suggest that SAPA-repeats modulate the trans-sialidase activity in blood.
Buscaglia
C A
CA
Instituto de Investigaciones Biotecnológicas, Universidad Nacional de General San Martín, Buenos Aires, Argentina.
Campetella
O
O
Leguizamón
M S
MS
Frasch
A C
AC
D000818:Animals; D019138:Antibodies, Blocking / Q000276:immunology; D000913:Antibodies, Protozoan / Q000276:immunology; D014355:Chagas Disease / Q000097:blood / Q000276:immunology*; D003001:Cloning, Molecular; D005260:Female; D006023:Glycoproteins / Q000235:genetics* / Q000276:immunology*; D016056:Immunodominant Epitopes / Q000502:physiology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009439:Neuraminidase / Q000235:genetics* / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology; D012091:Repetitive Sequences, Nucleic Acid / Q000502:physiology; D014349:Trypanosoma cruzi / Q000276:immunology*
D019138:Antibodies, Blocking; D000913:Antibodies, Protozoan; D006023:Glycoproteins; D016056:Immunodominant Epitopes; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; C069715:trans-sialidase; D009439:Neuraminidase